"It is not the fire who creates another fire, it is the heat of itself"

Discussion in 'General Science' started by Lightfire, Sep 19, 2011.

  1. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
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    Remind me of what my teacher said to us. As quoted above, I believe in this. But I have some few questions.

    1) Is there any attributes that a fire has that enable itself to burn something or make a another fire (by placing or putting it flammable thing) faster?

    2) If not, so it is the same as what "only heat" does? Both fire and "only heat" burn a specific or certain thing at the same time?

    3) For example I placed an incandescent lamp near an alcohol (Antiseptic 70%; can be bought in pharmacy store) (let's say the range between them is 3 inches), how many minutes does it take for the alcohol to form a fire?

    Thank you very much!
     
  2. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    O.O

    Your experiments are getting more and more dangerous, Catapult.... :p

    First of all, fire is only the reaction to heat. The heat really is what actually causes the fire. Generally incandescent lamps do not get hot enough to light things on fire unless the item has a very low combustion temperature.
     
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  3. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
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    Don't worry, none of the experiment I asked has never done before.:cool:

    So, an alcohol will cause a fire?:D
     
  4. DerStrom8

    Well-Known Member

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    *phew* Glad to hear that :D:p

    alcohol will not cause a fire. It would only be the heat, with a temperature high enough, that would light it. I don't know exactly what kind of alcohol you're talking about. You only say antiseptic 70%. It's hard to tell you at what temperature it would ignite, but incandescent light bulbs usually do not get hot enough.
     
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  5. Markd77

    Senior Member

    Sep 7, 2009
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    Think about the things that can start a fire; hot metal, like the coil in a car cigarette lighter, sparks, rubbing sticks together, compression of a gas like in a diesel engine. They are all hot things, but none of my examples involve a flame.
    Careful with the alchohol, sometimes it is hard to see that it is on fire, and the vapour can be explosive. Hopefully you do your experiments outside with nothing flammable around.
     
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  6. DerStrom8

    Well-Known Member

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    And NEVER try to light a bottle of a flammable liquid (alcohol)!!!
     
    Last edited: Sep 19, 2011
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  7. QuadTech

    New Member

    Apr 19, 2011
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    Markd77 raises a good point about the vapor. Sometimes you don't realize until it's too late!
     
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  8. GetDeviceInfo

    Senior Member

    Jun 7, 2009
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    fire requires 3 components, a fuel, heat, and an oxidant. Take any one away and the fire collapses. You should not attempt these types of experiments unsupervised. Certain fuels, in the presence of heat and oxidents, are violently explosive in nature.
     
  9. Wendy

    Moderator

    Mar 24, 2008
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    Actually if you mix any oxidant (ie, air) with a fuel you can get an explosion. Sawmills, where wood is turned into planks are at hazard all the time, as the saw dust hangs in the air. All it needs then is an ignition source.

    You can buy denatured ethanol alcohol at the hardware store (denatured means it has poison added). The burners made for this chemical burns very clean, and can do things like bend glass tubing.
     
  10. GetDeviceInfo

    Senior Member

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    you do need the third component, which is the heat.
     
  11. DerStrom8

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  12. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    I don't think that statement is totally correct either. A fire causes more than just heat, it causes air movement, sometimes quite a lot of air movement that can carry the fire upwards to start more fires and the drafts cause oxygen inrush etc. Fires also cause small burning particles to be spat out some distance and/or carried on updrafts.

    So the better quote would be;
    "It is not the fire who creates another fire, it is the heat of the fire, the drafts of the fire and the spread of burning embers from the fire itself"

    or if you simplify that,

    "It is the fire that creates another fire"
    ;)
     
  13. GetDeviceInfo

    Senior Member

    Jun 7, 2009
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    please correct as required;

    if one continues adding heat in the presence of a fuel and oxidant (in correct proportion), the point of ignition is reached. Once reached, the chemical action liberates addition heat causing neighbouring molecular groups to convert, and so on. Without that 'liberation' of heat, the original injection of heat would have to be continually added to convert the fuel. With that in mind, it could be said that fire (or the 'liberation' of heat) does in fact promote further coonversion. The rate is generally known as the 'flame front'. If it were not for this chemical liberation of heat (visually indicated by flame), the process would not continue, unless further heat was injected.

    Hence forth, I disagree with the original statement.

    Bill alluded to the fact that oxidation can take place at lower temperatures, and this conversion releases heat in the process. That heat can esculate to the point of combustion, resulting in self ignition, sometimes referred to as 'instantaneous combustion'.
     
    Last edited: Oct 11, 2011
  14. THE_RB

    AAC Fanatic!

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    I think you mean "spontaneous combustion"?
     
  15. GetDeviceInfo

    Senior Member

    Jun 7, 2009
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    yep. getting lost in my own thoughts.
     
  16. DerStrom8

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    Post removed
     
    Last edited: Jan 4, 2012
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